Routing error for named resources in IE6 only

This is a production problem with Rails 1.2.2. I have a sessions
controller with the following actions: new, create, destroy.

I am using named route resources, with a route like this in config/
map.resources *%w(post_states sessions)

In a layout, I have this logout link:
link_to 'logout', session_path(session), :method => :delete

When this link is clicked in FireFox on Windows XP or any Mac browser,
Rails does what is expected, it generates a call to the destroy method
of the sessions controller:

Processing SessionsController#destroy (for at 2007-03-12
20:13:20) [DELETE]
  Session ID: 45bbfc98cbfe99eaf4a03fbe8cf4a3a2
  Parameters: {"_method"=>"delete", "action"=>"destroy",
"id"=>"#<CGI::Session:0x9924024>", "controller"=>"sessions"}
Redirected to
Completed in 0.03335 (29 reqs/sec) | DB: 0.00000 (0%) | 302 Found

Here's the problem. When the link is clicked in IE6, Rails tries to
call the index action of the sessions controller:

Processing SessionsController#index (for at 2007-03-12
19:49:41) [DELETE]
  Session ID: 1011df9da58b75f0b2c9634dd3d44d49
  Parameters: {"_method"=>"delete", "action"=>"index",

ActionController::UnknownAction (No action responded to index)

Any insights would be appreciated. I have other controllers which
make delete requests on named controllers, and those actions run
without incident.

-- Jeff